Hello Mark,
Are you using the Standard version or the Pro version? If the Professional version, just type HI (for HIDE), or SHA (for SHADE). Or go to View (menu)->render->hide (or shade)
If using the standard version, bad luck: it doesn't support making real 3d objects. You can, of course, create FACEs (Draw->Surfaces->...)
Hope this helps.

You're welcome, Mack.
BTW if you're into making 3d views of houses, you could take a look at Sketchup (sketchup.google.com): I'm sure you'll have already heard of it. It complements Autocad/Intellicad (Zwcad) perfectly. The best thing is that, unlike Autocad/Intellicad, you can start out with the "block" shape and "ink" in the details as you advance in the design. And it's a helluva lot of fun!